The present disclosure relates to a multilayer ceramic capacitor and a circuit board structure having the multilayer ceramic capacitor.
Generally, electronic components using a ceramic material, such as a capacitor, an inductor, a piezoelectric element, a varistor, a thermistor, or the like, include a ceramic body made of a ceramic material, internal electrodes formed in the ceramic body, and external electrodes mounted on external surfaces of the ceramic body so as to be connected to the internal electrodes.
Among ceramic electronic components, a multilayer ceramic capacitor includes a plurality of stacked dielectric layers, internal electrodes disposed to face each other, having the dielectric layer interposed therebetween, and external electrodes electrically connected to the internal electrodes.
Multilayer ceramic capacitors have been widely used as components for mobile communications devices such as laptop computers, personal digital assistances (PDAs), mobile phones, and the like, due to advantages thereof such as a small size, high capacitance, and ease of mounting.
In accordance with the recent trend toward miniaturization and multifunctionalization of electronic devices, chip components also tend to be miniaturized and multifunctionalized. Therefore, demands have been made for multilayer ceramic capacitors having a small size and high capacitance.
In addition, a multilayer ceramic capacitor has been usefully used as a bypass capacitor disposed in a power supply circuit in a large scale integration (LSI) scheme. The multilayer ceramic capacitor serving as the bypass capacitor needs to effectively remove high frequency noise. This demand is further increasing in accordance with the trend in which electronic devices increasingly operate in a high frequency band. The multilayer ceramic capacitor used as the bypass capacitor may be electrically connected to a mounting pad on a circuit board through soldering, and the mounting pad may be connected to other external circuits through wiring patterns or conductive vias in the circuit board.
The multilayer ceramic capacitor includes equivalent series resistance (ESR) and equivalent series inductance (ESL) in addition to capacitance. These components of ESR and ESL deteriorate functions of the bypass capacitor. Especially, the ESL increases inductance of the capacitor in a high frequency band to thereby deteriorate the function of removing high frequency noise.
Meanwhile, in a case of a vertical multilayer capacitor, a low degree of ESL is required and, in order to achieve this, there has been proposed a method to form a margin region having no internal electrodes formed therein in a prefabricated ceramic laminate. However, the method may cause short-circuits.